Calking guns



H. B. COLLINS CALKING GUNS.

March 26, 1957 2 Sheets-Sheet 1 Filed Dec. 21, 1954 INVENTOR.

Harold B. Col/ins RENT,

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March 26, 1957 H. B. COLLINS CALKING GUNS 2 Sheets-Sheet 2 Filed Dec. 21; 1954 I Harold 5. Collins INVENTOR.

BY I Aumuqs CALKING GUNS Harold B. Collins, Breedsville, Mich.

Application December 21, 1954, Serial No. 476,675

9 Claims. (Cl. 22280) My invention relates to improvements in calking guns of the type in which movement of an operating lever nited States Patent moves a plunger forwardly against a follower in a calking compound cartridge to compress and discharge the compound out of the cartridge and the plunger is held by a releasable clutch plate in its forwardly moved position.

In this type of calking gun, the calking compound oozes and drips from the cartridge after-a calking sequence of operations when it is desired to stop the flow of calking material and because of back pressure of the compressed compound against the follower. This results in loss and waste of the compound.

Having the foregoing in mind, it is the primary object of my invention to provide in such guns means for relieving back pressure in the cartridge so that at the end of each calking or sequence of calking operations, no dripping of the compound from the cartridge will occur with the resultant mess and the full contents of the cartridge used for neat clean calking operations.

Another object is to provide means for automatically accomplishing the foregoing by suction and follower puncturing means on theplunger.

Still another object is to provide for relieving back pressure for the purpose set forth by suction means on the plunger rendered effective by rearward movement of the plunger and for automatically operating the releasing clutch plate into releasing position to permit rearward movement of the plunger from its forwardly moved or advanced position.

Other and subordinate objects together with the precise nature of my improvements will become apparent when the following description and claims are read with reference to the accompanying drawings in which:

Figure l is a view in perspective of the calking gun having my invention embodied therein;

Figure 2 is a fragmentary enlarged view in plan of the same;

Figure 3 is a view in transverse section taken on the line 3-3 of Figure 2;

Figure 4 is a view in longitudinal section with the parts in normal position; and

Figure 5 is a similar view illustrating the manner in which the invention operates.

Referring to the drawings by numerals, the calking gun illustrated therein as embodying my invention comprises a trough-shaped magazine 1 for holding the conventional cartridge 3 of calking compound 4 between a rear cap 5 on the rear end of the magazine and a stop plate 7 on the front end of said magazine vertically slotted, as at 9, for extension of the nozzle 11 of the cartridge 3 therethrough. A channeled piston grip 13 is secured by rivets 15 to the cap 5 behind the same.

An operating lever 17 is pivoted intermediate its ends, as at 19, in the pistol grip 13 for operation rearwardly below its pivot from a normal position shown in Figure 4 in which it extends forwardly out of the pistol grip. A hairpin spring 21 on the pivot 19 and engaging said pis- Patented Mar. 26, 1957 tol grip 13 and lever 17 urges said lever into normal position.

The operating lever 17 is operatively connected to a plunger rod 23 slidably extended through the hand grip 13 and cap 5 into the magazine 1. The operating connections comprise an apertured driving clutch plate 25 through which the plunger rod 23 extends and which is tiltable on said rod 23 from a releasing position into an inclined position to clutch said rod, A coil spring 27 on said rod is interposed between the driving clutch plate 25 and an apertured abutment plate 29 in the pistol grip 13 and urges the driving clutch plate 25 into releasing position against the back of the pistol grip 13. The plunger rod 23 slides through and is guided by the abutment plate 29.

A link 31 pivoted, as at 33, to the operating lever 17 above the pivot 19 and slidably guided in an aperture 35 in the back of the pistol grip 13 is operatively connected to the driving clutch plate 25 to tilt said plate by a notch 37 straddling an edge of said plate 25.

An apertured holding clutch plate 39 for the plunger rod 23 and through which said rod slidably extends is pivoted at its upper end on the cap 5 between said cap nd the operating lever 17 for tilting from a rearwardly swung rodclutching position into a forwardly swung rod releasing position in opposition to a coil spring 41 interposed between said cap 5 and plate 39.

As will be understood in the described type of cal ing gun, upon rearward operation of the operating lever 17 from normal position, the link 31 tilts the driving clutch plate 25 into clutching position and moves said plate forwardly to impart a forward step of movement to the plunger rod 23, as shown in Figure 5, and upon return of said lever 17 to normal position, the driving clutch plate is released and returned rearwardly by spring 27, the plunger frictionally engaging the holding plate 39 to swing the same forwardly into rod releasing position, and said holding clutch plate 39 during return of the operating lever 17 and driving clutch plate 25 to normal position being swung rearwardly by the spring 41 into clutching position to prevent rearward movement of said rod 23 from its forwardly driven position.

According to my invention, the plunger rod 23 is provided on a reduced front end 43 thereof forming a shoulder 45 with a forwardly opening deformable piston cup 47 of resilient material frictionally fitting in the cartridge 3 behind the follower 49 and backed by a disk 53 on said end 43 seating rearwardly against the shoulder 45. A puncturing element in the form of a conical cap nut 55 is threaded onto the reduced end 43 against a washer 57 on said end and secures the piston cup 47, collar 51 and disk 53 in place. The nut 55 is set back in the piston cup 47 so that the rim of said cup engages the follower 49 ahead of the nut 55. The operating lever 17 in its normal position engages the lower end of the holding clutch plate 39 and swings it forwardly into releasing position.

When the gun is operated in the manner previously described to move the plunger rod 23 forwardly, the rim of the piston cup engages the follower 49, as shown in Figure 4, and the collar 51 pushes the back of the piston cup 47 forwardly and the puncturing nut 55 through the follower 49 to puncture the same as shown in Figure 5. When the back of the piston cup 47 is thus pushed forwardly, said piston cup 47 folds rearwardly over the collar 51 so that it collapses as shown in Figure 5 and tends to react and expand rearwardly into normal cup form. Then, the plunger compresses and discharges the compound 4. At this point, if the operating lever 17 is released, it snaps under the urge of the spring 21 forwardly into normal position, engages the lower end of the holding clutch plate 39 and impacts the same to swing said plate temporarily into rod releasing position During temporary release of the plunger rod 23, the cup piston 47 reacts and expands into normal position and moves the plunger rod 23 rearwardly correspondingly thereby withdrawing the puncturing nut 55 from the puncture 59 in the follower 49 and creates suction at said puncture to relieve back pressure behind the compound 4 in the cartridge 3 thereby preventing the compound 4 from dripping out of the nozzle 11 while the gun is not in operation. As will be seen, the cup piston acts as a suction pump to relieve the back pressure.

The foregoing is a detailed description of a preferred embodiment of my invention and will, it is believed, suifice to impart a clear understanding thereof.

Manifestly, the invention is susceptible of modification without departing from the inventive concept and right is herein reserved to such as fall within the scope of the appended claims.

What I claim is:

1. In a calking gun having a magazine for holding a cartridge of calking compound provided with a forwardly movable follower for compressing and discharging said compound, a plunger rod movable forwardly to move said follower and also movable rearwardly, and an opcrating lever pivoted for swinging from a normal position to move said rod forwardly, means for relieving back pressure in said cartridge resulting from expansion of the compressed compound comprising a puncturing element on said rod advanced and retracted by forward and rearward movement of said rod to puncture the follower and withdraw out of said puncture, and a resilient suction member on said rod engaging said follower and collapsible upon forward movement of said rod and expanding to create suction at said puncture and move said rod rearwardly to withdraw said element.

2. The combination of claim 1, and a releasable holding member normally preventing rearward movement of said rod, said lever being spring loaded to swing into normal position and impact and release said holding member.

3. The combination of claim 1, said suction member comprising a suction cup.

4. The combination of claim 1, said puncturing element comprising a conical nut on said rod.

5. The combination of claim 1, said suction member comprising a suction cup, and a collar on said rod backing said cup and exerting pressure against said cup to collapse the same.

6. The combination of claim 1, and a releasable holding member normally preventing rearward movement of said rod, said lever being spring loaded to swing into normal position and impact and release said holding member, said puncturing element comprising a conical nut on said rod inside said cup.

7. In a calking gun having a magazine for holding calking compound, a plunger rod movable forwardly for compressing and discharging said compound and also movable rearwardly, and an operating lever pivoted for swinging from a normal position to move said rod forwardly, means for relieving back pressure in said magazine resulting from expansion of the compressed compound comprising a resilient suction member on said rod collapsible upon forward movement of said rod and expanding to move said rod rearwardly and to create suction on said compound.

8. In a calking gun having a magazine for holding a cartridge of .calking compound provided with a forwardly movable follower for compressing and discharging said compound, a plunger rod movable forwardly to move said follower and also movable rearwardly, and an operating lever pivoted for swinging from a normal position to move said rod forwardly, means for relieving back pressure in said cartridge resulting from expansion of the compressed compound comprising a resilient suction member on said rod engaging said follower and collapsible upon forward movement of said rod and expanding to move said rod rearwardly and to create suc tion in said compound through a hole in said follower.

9. The combination of claim 8, and a puncturing element on said rod advanced and retracted by forward and rearward movement of said rod to puncture a hole in said follower and withdraw out of said hole.

References Cited in the file of this patent UNITED STATES PATENTS 1,117,730 Webb Nov. 17, 1914 1,540,182 Outhier et a1. June 2, 1925 2,022,706 Clark Dec. 3, 1935 2,582,156 Peterson Jan. 8, 1952 

